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We propose a new approach called LiDAR-Flow to robustly estimate a dense scene flow by fusing a sparse LiDAR with stereo images. We take the advantage of the high accuracy of LiDAR to resolve the lack of information in some regions of…

Computer Vision and Pattern Recognition · Computer Science 2019-12-16 Ramy Battrawy , René Schuster , Oliver Wasenmüller , Qing Rao , Didier Stricker

Optical Remote Sensing Image Salient Object Detection (ORSI-SOD) remains challenging due to complex backgrounds, low contrast, irregular object shapes, and large variations in object scale. Existing discriminative methods directly regress…

Computer Vision and Pattern Recognition · Computer Science 2026-04-27 Haojing Chen , Zhihang Liu , Yutong Li , Tao Tan , Haoyu Bian , Qiuju Ma

Deflection of light along the optical path is a major source of image degradation for ground-based telescopes. Methods have been developed to measure upper atmospheric seeing based on models of the turbulence in the atmosphere, but due to…

Instrumentation and Methods for Astrophysics · Physics 2025-08-04 Meghan A. Marangola , Elana K. Urbach , Christopher W. Stubbs

The point spread function (PSF) serves as a fundamental descriptor linking the real-world scene to the captured signal, manifesting as camera blur. Accurate PSF estimation is crucial for both optical characterization and computational…

Computer Vision and Pattern Recognition · Computer Science 2026-01-13 Jiajian He , Enjie Hu , Shiqi Chen , Tianchen Qiu , Huajun Feng , Zhihai Xu , Yueting Chen

We describe a self calibrating optical technique that allows to perform absolute measurements of scattering cross sections for the light scattered at extremely small angles. Very good performances are obtained by using a very simple optical…

Optics · Physics 2009-11-10 Doriano Brogioli , Alberto Vailati , Marzio Giglio

A new combined sub-filter scale turbulence and shock-capturing model is developed for high-order finite volume numerics, extending previous work to unstructured solvers. Block Spectral Stresses (BSS) method relies on the spectra of the…

Fluid Dynamics · Physics 2024-03-01 Matteo Ruggeri , Victor C. B. Sousa , Carlo Scalo

The dynamics of spherical laser-induced cavitation bubbles in water is investigated by plasma photography, time-resolved shadowgraphs, and single-shot probe beam scattering enabling to portray the transition from initial nonlinear to late…

Fluid Dynamics · Physics 2022-04-27 Xiao-Xuan Liang , Norbert Linz , Sebastian Freidank , Guenther Paltauf , Alfred Vogel

We report a new approach to flow field tomography that uses the Navier-Stokes and advection-diffusion equations to regularize reconstructions. Tomography is increasingly employed to infer 2D or 3D fluid flow and combustion structures from a…

Fluid Dynamics · Physics 2026-03-31 Joseph P. Molnar , Samuel J. Grauer

A coherent phase-contrast optical system has been designed and tested for tomographic imaging of pressure fields from experimental transient acoustic signals. The system is similar to the pulsed, central-order schlieren method, but uses a…

Optics · Physics 2014-07-21 G. T. Clement , S. V. Letcher

In this work we present a dedicated experimental facility and an image-based method for measuring water depth in a radially spreading dam-break wave propagating over a horizontal plane. The facility consists of a prismatic reservoir…

Fluid Dynamics · Physics 2026-01-27 Elia Buono , Roberto Bosio , Andrea Cagninei , Davide Poggi

Investigation of external flows past arbitrary objects requires access to the information in the boundary layer and the inviscid flow to paint a full picture of their characteristics. However, in laser diagnostic techniques such as particle…

Fluid Dynamics · Physics 2023-10-09 Shuangjiu Fu , Shabnam Raayai-Ardakani

This paper presents a high speed implementation of an optical flow algorithm which computes planar velocity fields in an experimental flow. Real-time computation of the flow velocity field allows the experimentalist to have instantaneous…

Fluid Dynamics · Physics 2013-09-26 N. Gautier , J-L. Aider

Particle Image Velocimetry (PIV) typically relies on cross-correlation,which makes it difficult to obtain instantaneous velocity fields that are both spatially dense and available in real time at high acquisition rates. Optical Flow…

Fluid Dynamics · Physics 2026-05-22 Juan Pimienta , Jean-Luc Aider

We report on the direct measurements of fluid flow vorticity using a spatially shaped beam with a superposition of Laguerre-Gaussian modes that reports on the rotational Doppler shift from microparticles intersecting the beam focus.…

Optics · Physics 2016-06-29 A. Ryabtsev , S. Pouya , A. Safaripour , M. Koochesfahani , M. Dantus

The present study investigated the flow birefringence induced by shear components along a camera's optical axis, which has been neglected in conventional theories of photoelastic measurements. Measurements were conducted for a wide range of…

The Depth from Defocus (DFD) imaging technique for measuring the size and number concentration of particles in a dispersed two-phase flow has up to now been restricted to relatively sparse particle densities and to identifying only…

Fluid Dynamics · Physics 2024-04-01 Rixin Xua , Zuojie Huanga , Wenchao Gonga , Wu Zhoua , Cameron Tropea

Cylindrically or spherically focusing shock waves have been of keen interest for the past several decades. In addition to fundamental study of materials under extreme conditions, cavitation, and sonoluminescence, focusing shock waves enable…

Depth map estimation is a crucial task in computer vision, and new approaches have recently emerged taking advantage of light fields, as this new imaging modality captures much more information about the angular direction of light rays…

Computer Vision and Pattern Recognition · Computer Science 2020-08-12 Yang Chen , Martin Alain , Aljosa Smolic

We propose DistSurf-OF, a novel optical flow method for neuromorphic cameras. Neuromorphic cameras (or event detection cameras) are an emerging sensor modality that makes use of dynamic vision sensors (DVS) to report asynchronously the…

Image and Video Processing · Electrical Eng. & Systems 2020-03-31 Mohammed Almatrafi , Raymond Baldwin , Kiyoharu Aizawa , Keigo Hirakawa

Neural optical flow (NOF) offers improved accuracy and robustness over existing OF methods for particle image velocimetry (PIV). Unlike other OF techniques, which rely on discrete displacement fields, NOF parameterizes the physical velocity…

Fluid Dynamics · Physics 2026-03-31 Andrew I. Masker , Ke Zhou , Joseph P. Molnar , Samuel J. Grauer